Occurrence and human exposure assessment of bisphenol analogues in various paper products from Korea

Bisphenol A (BPA) has been widely used in various paper products, particularly as a color developer in thermal receipts. Growing concerns about its toxicity have prompted the introduction of other bisphenols as alternatives. This study investigated the occurrence and residue levels of BPA and its analogues in thermal paper receipts (n = 120) and other paper products (n = 32) collected in Korea in 2015, with a particular focus on business-type-specific differences during an early phase of BPA substitution. BPA was the dominant compound in most receipts, while bisphenol S (BPS) was the most common substitute in "BPA-free" labeled receipts. Total concentrations of bisphenol analogues in thermal receipts were 2-4 orders of magnitude higher than those in other paper products. Multivariate analysis identified distinct compositional clusters associated with different color developers. Large retail chains showed a higher prevalence of BPS-based receipts, whereas small local stores predominantly relied on BPA-based thermal papers, indicating business-type-specific differences in substitution timing. Dermal exposure estimates indicated that occupational groups, particularly workers in small local stores, experienced substantially higher exposure than the general population. Estimated BPA intakes via paper handling exceeded the revised tolerable daily intake proposed by the European Food Safety Authority, highlighting the need for comprehensive exposure assessments of bisphenol analogues, especially in occupational settings.